
Geometric models of virtual environments 333
Figure 14.15 Types of triangle configurations
Figure 14.16 Deletion of a vertex from a mesh
Figure 14.17 Deletion of an edge from a mesh, known as edge collapse method
type of algorithm can also be used when we want to refine a mesh). The first operator
simply removes a vertex, as shown in figure 14.16. However, a large number of degrees
of freedom remain on this operator: the re-triangulation shown in the figure is just one
example of triangulation.
To compensate this disadvantage, there is another type of operator, called edge
collapse, shown in figure 14.17. In this way, the only freedom that remains